Art of treating asphalt.



J. A. W. PINE & W. B. RUGGLBS.

ART 0F TREATING ASPHALT. APPLICATION FILED Nov. e, 1909.

Patented Apr. 1, 1913.

GSS 5.56

JIA. 7K6" WTNESSES ATTORNEYS JAMES A. W. PINE AND WILLIAM IB. RUGGLES, 0F NEW YORK, N. Y.

ART 0F TREATING ASPHALT.

Specication of Letters Patent.

Application filed November 6, 1909. Serial No. 526,869.

To all whom t may concern:

Be it known that we, JAMES A. W. PINE and WILLIAM B. RUGGLES, citizens of the United States, residing at New York city, in the county of New York and State of New York, have invented certain new and useful Tmprovements in the Art of Treating Asphalt, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to the art of treating asphalt and, more specilically to the art of preparing asphalt aving material from crude Trinidad asphallt.

One of the objects thereof is the practical and economical handling of crude Trinidad asphaltor an asphalt of that character and generalv composition.

Another object thereof is to provide an asphalt paving material prepared in a simple and inexpensive manner.

Other objects will be in -part obvious and y in part pointed out hereinafter.

The invention accordingly consists of the several steps and the relation and order of each of the same with respect to one or more of the others thereof, as will be set forth in the following description, and the scope of` the application of which will be indicated in the appended claims.

The drawing graphically illustrates the several steps. of the art, the dotted lines in- .dicating that certain of said steps may be entirely omitted, or occur in altered relation to the other steps thereof.

In order to render certain features of this invention more readily and fully understood, it may be here noted that natural asphalt of the class known as Trinidad asphalt is a natural deposit of approximately thefollowing composition: water (probably sea-water), 27-30% bitumen, 37%; mineral matter (clay and fine sand), S23-38%,. There is also present an appreciable quantity of varions soluble salts. It has been found desirable in practice to reduce the high percentage of water to a minimum, as the retention vthereof adds greatly to the expense of shipment of the asphalt from the place of deposit to the oint-at which it is desired to make use o the same.' It has further been found that the presence of soluble salts has a deteriorating eect upon asphalt pave-4 ments, being, in fact supposed to be the cause of the so-called rotting of pavement having that material as afcementing agent. If it be attempted to dispel the said water from the crude as halt by the application of heat it will be und a very tedious and costly operation and, moreover, as relatively high temperatures will be found necessary, because of the natural nonconductivityof the asphalt, there will result a tendency to Scorch o-r burn the asphalt itself and thereby impair many of the valuable qualities thereo By this. invention suiiciently thorough drying is attained, soluble salts, if desired, may be washed out and a paving material of superior quality is produced; moreover these beneficial results are reached in a simple, practical, and economical manner.

The various steps employed in following out the art of the present invention will now be described. Y

First the crude asphalt is groundfpulverized or otherwise comminuted to any desired degree of tin'eness by the aid of any lsuitable means, after which it is agitated in water to separate therefrom, if desired, soluble salts inherent in its composition. It is to be understood that the washing may be accomplished without agitation, and, if found desirable, by the use of solvents other than water. The washed or unwashed asphalt is then dried either by evaporation 1n the atmosphere or by exposure to heat in any drier suitable for that purpose. Preferably a mechanical drier is employed because of its applicability to this kind of heating. it has been found that when the pulverized asphalt is dried by artificial heating a degree of temperature is liable to be reached at which there is a'tendency for the granular particles to become sticky, adhere and run together. This is found to occur at and above 150 F., which temperature may not be sufficiently high to efliciently and expeditiously dispel the moisture. The addition of -a small percentage of a refractory powdered substance, as marl, to the granular asphalt, either precedent to or simultaneously with its introduction into the drier servesto effectively reclude the adhesion of the particles thereo and to render possible the raising of the temperaturev to or slightly above the boiling point of water, whereupon a largefpercentage of the moisture is qulckly and cheaply evaporated.

The introduction of powdered marl or other similar substance is otherwise advantageous, in that. it prevents the particles of the asphalt from sticking together in transit, under varying conditions of temperature, when the said material is shipped in bulk or packed in bags. As a next step in carrying out the said art of preparing paving material, suitable sand is heated, as in rotary drums, to a temperature varying from about 350 to 500 F., and this hot sand together with aV percentage of stone dust or other fine mineral matter is dumped into a mechanical mixing machine into which is introduced, in proper proportion, cold, comminuted, (washed if desired) dried Trinidad asphalt. ln practice about 15% of this asphalt is mixed with 85%, more or less, of the sand or mineral matter, which has been heated to a temperature of from 350 to 500 F. Thereupon there ensues a thorough andnniform mixing of the two granular substances and at the same time the heat imparted to the cold asphalt by the much larger quantity of hot sand will very quickly drive oft whatever moisture there may be still remaining in the asphalt. Fluxing material, usually petroleum residuum of from 14 to 22 Baume gage, in either hot or cold condition, is added before, simultaneously with, or immediately after the cold granular asphalt is introduced into the mixer containing the hot sand and afterv a few minutes mixing in the machine a very uniform and superior asphalt paving material is obtained. The heat of the entire mass can be readily maintained at or above 325 F., at which temperature the material is in suitable condition for hauling to and laying on the street.

It will be understood that by the addition of a suitable solvent to eomminuted (Washed if desired), dried Trinidad asphalt an asphaltic cement is obtained which may be used for paving and other purposes without the necessity of heating either the asphalt tended to be mixed and this is accomplished in a very simple and inexpensive manner,

n a very simple and inexpensive manner, without resorting to the use of extensive and costly plants such as are necessitated by the methods now generally employed in the refining and utilization of Trinidad asphalt. In this connection, itv will be noted, that heretofore Trinidad asphalt has been used in a hot fluid condition, with the addition thereto of various mineral substances, to form a bituminous concrete. The present invention comprehends the preparation of a dry granular or powdery bituminous cement which may be readily shipped in bags or in bulk. This cement may be heated, or treated with a solvent in order to bring out its cementitious qualities and it is then only necessaryto mix in proper mance? quantities with suitable mineral matter to obtain an inexpensive and durable bituminous concrete.- lt will therefore be seen that the present invention is well adapted to attain the advantages hereinbefore set forth, in a simple, efficient, and inexpensive manner.

lt is to be understood that by the term Trinidad asphalt, is meant, in the present specification and claims, not only that composition of bitumen and mineral matter which is at the present time principally obtained from the so-called pitch lake in the island of Trinidad, British TWest lndies, but also any bituminous substance having approximately like composition and characteristics. It is to be noted that the expressions cold and at ordinary temperatures occurring in the. claims are employed to denote the fact that the dry granular asphalt is mixed at its existing temperature, without preheating, with the preheated mineral matter and fluxing agent.

As the above art could be carried out by means of various kinds of apparatus and could be varied without departing from the scope of this invention, and as man features of the above art are of indepen ent value, it is intended that all matter contained in the above description shall be interpreted as illustrative 'and not in a limiting sense. It is also to be understood that the language used in the following claims is intended to cover all of the genericpan'd' specific features of the invention herein de# scribed and all statements of the sco e of the invention, which, as a matter o language, might be said to fall therebetween.

Having described our invention, what we claim as new and desire to secure by Letters Patent is:

l. The improvement in the art of preparing paving material which comprises comminuting crude Trinidad asphalt, agitating in water to remove soluble salts, and then subjecting same to a drying process embodying an application of heat at a sufficiently low temperature to maintain the asphalt in a l`gramilar condition.

:2. The improvement in the art of preparing paving material which comprises comminuting crude Trinidad asphalt, adding thereto an agent adapted. under ordinary conditions of handling at. temperatures below a certain predetermined teinperatureto prevent adhesion of the particles thereof and then subjecting the mixture to a dryingr process embodying an application of heat at a temperature below the said predetermined temperature.

3. The improvement in the art of preparing' paving material which comprises comminuting crude Trinidad asphalt, Washing in water to remove soluble salts, adding thereto a refractory powder adapted to pre- Iico . granular form; then mixing in granular Iso adhesion, and subjecting same to a drying vent granular adhesion, and drying by the application of heat thereby providing an asphalt having a granular structure.

4. The improvement in the art of preparing paving material which comprises commmuting crude Trinidad asphalt, washing said asphalt, and drying at a suiiiciently low temperature to maintain the asphalt in granular form, then mixing the same cold with hot crushed mineral matter.

5. The improvement in the art of preparing paving material which comprises comminutin crude Trinidad asphalt, Washing said asp alt in Water and drying at a suiicient-ly low temperature to maintain the asphalt in granular form, then adding there-- to a petroleum tluxand mixing at ordinary temperatures With proper proportions of hot san and other reduced mineral matter.

6. The improvement in the art of preparing paving material Which comprises commlnuting crude Trinidad' asphalt, subjecting the same to a drying process embodying an application of heat at a sutliciently low temperature to maint-ain the asphalt in form, at a relatively low temperature, with ffine heated mineral-matter and a petroleum ux. l

7. Theimprovement in the art of preparing paving material which comprises comminuting crude Trinidad asphalt, drying the same by the application of heat at a suiiiciently low temperature to maintain the asphalt in granular form, then mixing in granular form, at a relatively low temperature, with hot sand and a petroleum ux.

8. The improvement in the art of preparing paving material which comprises comminuting crude Trinidad asphalt, adding thereto an agent adapted under ordinary conditions of handling to prevent granular process at a suiiiciently low temperature to maintain the granular condition thereof adding thereto a petroleum iux and mixing cold with hot iine mineral matter.

9. The improvement in the art of preparing paving material which comprises comminuting crude Trinidad asphalt, Washing said asphalt in Water, adding thereto an agent adapted to prevent granular adhesion, drying by the application of heat, adding thereto a petroleum flux, and mixing cold With proper quantites Aof hot sand and crushed mineral matter.

10. The improvement in the art of preparing paving material which comprises comminuting crude Trinidad asphalt, Washing said asphalt, adding thereto an agent adapted to prevent granular adhesion, drying, adding thereto a petroleum flux, and i cold With hot sand or other fine matter.

1l. The improvement in the art of preparing bituminous cement which comprises comminuting crude Trinidad asphalt, add- 1ng thereto an agent adapted under ordinary conditions of handling at all temperatures below a certain predetermined temperature, to prevent granular adhesion, and

mineral ldrying by the application of heat at a temperature below the said predetermined temperature.

l2. The improvement in the art of preparing bituminous concrete which comprises .comminuting crude Trinidad asp-halt, drylng by applying heat at a suiiiciently low temperature to preserve the granular condition thereof, adding a solvent thereto and mixing at 'ordinary temperatures with mineral matter.

13. The improvement in the art of preparing paving material, which comprises comminuting crude Trinidad asphalt and Subjecting said asphalt to a drying process, embodying an application of heat, employing the heating medium at a temperature adapted to preserve the granular condition -of the asphalt.

14. The improvementin the art of preparing paving material which com rises comminuting crude Trinidad aspha t, subjecting said asphalt to a drying process embodying an application of heat at a temperature mixing adapted to preserve the granular condition of the asphalt, and mixing the same with hot crushed mineral matter.

In testimony whereof We aiiix our signatures, in the presence of two Witnesses.

JAMES A. W. PINE. `WILLIAM B. RUGGLES.

Witnesses:

LAURA E. SMITH, ARCHIBALD K. TOWERS.

1t is hereby certified that in Letters Patent No. 1,057,667, granted April l, 1913, upon the application of James A. W. Pine and William B. Ruggles, of New York, NQ'YL., for an improvement in The Art of Treating Asphalt, errors appear in the printed specification requiring correction as follows: Page 2, line 47, strike out the syllables tended and insert the'words or the mineral matter with which it is intended; same page, strike out line 49, as now numbered; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the casein the Patent Uoe.

Signed and sealed this 20th day of May, A. D., 1913.

l' o. o. Bunnies,

Acting @ammissiomr oflaatenis. I

[SEAL] 

